Servo motor system and method

ABSTRACT

A servo motor system and method has been developed to provide speed, orientation, location, and/or direction detection using a single inductive sensor. Direction, orientation, speed, and/or location detection are detected using a single channel inductive sensor in a servo motor control system. Mechanical control systems using servo motors are easily upgraded with added safety, precision control, and automation using the inductive sensor system described herein.

RELATED APPLICATIONS

This application is a continuation-in-part of allowed U.S. patentapplication Ser. No. 15/844,870 filed on Dec. 18, 2017, now U.S. Pat.No. 10,161,764 which is a continuation-in-part of granted U.S. patentapplication Ser. No. 15/143,508, now U.S. Pat. No. 9,874,460 filed onApr. 30, 2016 which are hereby incorporated by reference.

BACKGROUND Summary

A servo motor system includes one or more magnets fixed to a movingcomponent of the servo motor system, each of the one or more magnetshaving a north pole and a south pole aligned to alternately induce amagnetic field into a face of an inductive sensor; a processor andmemory non-transitively programmed to: determine an ON time of theinductive sensor as a result of moving the north pole and the south poleof each of the one or more magnets past the inductive sensor in anunknown direction; determine the unknown direction to be a known firstdirection or a known second direction when the ON time is equal to apredetermined threshold associated with the first known direction or apredetermined threshold associated with the second known direction; andone or more servo motors that receive control signals as a result of themoving of the north poles and the south poles of each of the one or moremagnets past the inductive sensor, wherein the one or more servo motorscause motion of a mechanical system. The mechanical system may be arobotic arm, an assembly line, or an electro-mechanical machine. Theunknown direction may be a rotational direction or a linear direction ofmovement. The inductive sensor, in combination with a processor orcontroller, may additionally detect speed, orientation, and/or positionof a rotating or linearly moving component. The inductive sensor may bea Hall Effect sensor. The inductive sensor may be mounted to a servomotor or to a servo motor cover. The face of the inductive sensor may bepositioned perpendicular to a north-south direction of each of the oneor more magnets. The face of the Hall Effect sensor may be positionedbetween 1 and 0.010 of an inch from a surface of the one or moremagnets. The servo motor speed of rotation may be between 1 and 20,000rotations per minute. The one or more magnets may be attached to arotational drive system. The servo motor system may additionallycomprise one or more cable drive systems. The inductive sensor mayprovide direction, position, and/or location of at least one cable ofthe cable drive systems. The inductive sensor may provide signals thatimprove safety and control of the mechanical system. Positional safetythreshold parameters related to direction of rotation, position, and/ororientation may used to achieve improved safety and control of themechanical system. A load weight or torque of a mechanical system may bedetermined using signals from the inductive sensor and motor current.The load weight may be a weight exerted on the one or more cable drivesystems. The mechanical system may comprise two or more cable drivesystems. The mechanical device may be a manufacturing tool. Themechanical system may be controlled in part by feedback produced by theinductive sensor.

Apparatus and methods in accordance with the invention have beendeveloped to provide direction detection of a moving object or movingcomponent using a single inductive sensor. Direction detection, speeddetection, and location detection may each be provided by the sameinductive sensor and used as feedback in a motion control system.Control systems of tractors, draglines, power shovels, and cranes may beeasily upgraded with added safety, precision control, and automationusing an inductive sensor system as disclosed herein. The features andadvantages of the invention will become more fully apparent from thefollowing description and appended claims.

A tractor device with one or more magnets fixed to a moving component ofthe tractor device, each of the one or more magnets having a north poleand a south pole aligned to alternately induce a magnetic field into aface of an inductive sensor. A processor and memory non-transitivelyprogrammed to determine an ON time of the inductive sensor as a resultof moving the north pole and the south pole of each of the one or moremagnets past the inductive sensor in an unknown direction, determine theunknown direction to be a known first direction or a known seconddirection when the ON time is equal to a predetermined thresholdassociated with the first known direction or a predetermined thresholdassociated with the second known direction. One or more motors receivecontrol signals as a result of the moving of the north poles and thesouth poles of each of the one or more magnets past the inductivesensor. The tractor device may be a dragline, power shovel, or a crane.The unknown direction may be a rotational direction. The unknowndirection may be a linear direction. The inductive sensor may be usedfor additional detection of speed and position. The inductive sensor maybe a hall effect sensor. The inductive sensor may be mounted within arotating cover. The face of the inductive sensor may be positionedperpendicular to a north-south direction of each of the one or moremagnets. The face of the hall effect sensor may be positioned between 1and 0.010 of an inch from a surface of the one or more magnets. A speedof the rotation direction may be between 1 and 20,000 rotations perminute. The one or more magnets may be attached to a rotational drivesystem of the tractor device. The tractor device may additionallycomprise one or more cable drive systems. The inductive sensor mayprovide direction, position, and location of at least one cable of thecable drive systems. The inductive sensor may provide signals thatimprove safety and control of the tractor. Positional safety thresholdparameters related to direction of rotation may be used to achieveimproved safety and control. A load weight may be determined usingsignals from the inductive sensor and motor current. The load weight maybe a weight exerted on the one or more cable drive systems. The tractordevice may comprise two or more cable drive systems. The tractor devicemaybe a mining tractor. The mining tractor may be controlled, in part,by feedback produced by the inductive sensor.

A system and method is provided for detection of a direction of movementof a component using a single inductive sensor. The component may be arotational component such as a motor, shaft, gear, or the like. An ONand/or OFF time of the inductive sensor is measured as north and southpoles of one or more magnets are moved past a face of the inductivesensor. A directional correlation is established which allows fordetermination of an unknown direction of movement.

Consistent with the foregoing, a system and method for providingdirection detection of a moving object or moving component is disclosed.Such a system includes a rotational component with one or more magnetsfixed thereto, a power source for powering the inductive sensor, and aprocessor configured to determine an ON time and OFF time of theinductive sensor as the moving component rotates the north and southpoles of each of the one or more magnets past a face of the inductivesensor. A corresponding method is also disclosed and claimed herein.

BRIEF DESCRIPTION OF THE DRAWINGS

In order that the advantages of the invention will be readilyunderstood, a more particular description of the invention brieflydescribed above will be rendered by reference to specific embodimentsillustrated in the appended drawings. Understanding that these drawingsdepict only typical embodiments of the invention and are not thereforeto be considered limiting of its scope, the invention will be describedand explained with additional specificity and detail through use of theaccompanying drawings, in which:

FIG. 1 is a top view showing an embodiment of a moving component withmore than one magnet and an inductive sensor in accordance theinvention;

FIGS. 2a and 2b are timing diagrams of directional ON and OFF outputs ofan inductive sensor in accordance with an embodiment of the presentinvention;

FIG. 3 is a perspective view of a moving component with more than onemagnet and an inductive sensor in accordance with an embodiment of theinvention;

FIG. 4 is a top view of a moving component with more than one magnet andan inductive sensor in accordance with an embodiment of the invention;

FIG. 5 is a perspective view of a moving component with more than onemagnet and an inductive sensor in accordance with an embodiment of theinvention;

FIG. 6 is a perspective view of a moving component with more than onemagnet and an inductive sensor in accordance with an embodiment of theinvention;

FIG. 7 is a top view of a moving component with more than one magnet andan inductive sensor in accordance with an embodiment of the invention;

FIG. 8 is a top view of a split rotational moving component with morethan one magnet in accordance with an embodiment of the invention;

FIG. 9 is a top view of a moving component with more than one magnet andan inductive sensor in accordance with an embodiment of the invention;

FIG. 10 is a top view of an extruded rotational cylinder with aninductive sensor and magnets in an inner area of the cylinder;

FIG. 11 is a schematic flow diagram of a system for determiningdirection in accordance with an embodiment of the invention;

FIG. 12 is a side view of a power shovel in accordance with anembodiment of the invention;

FIG. 13 is a side view of a dragline in accordance with an embodiment ofthe invention;

FIG. 14 is a side view of a crane in accordance with an embodiment ofthe invention;

FIG. 15 is a flow diagram of a servo motor control system and method inaccordance with an embodiment of the invention;

FIG. 16 is a flow diagram of a servo motor control system and method inaccordance with an embodiment of the invention;

FIG. 17 is a flow diagram of a servo motor control system and method inaccordance with an embodiment of the invention; and

FIG. 18 is a perspective view of a servo motor in accordance with anembodiment of the invention.

DETAILED DESCRIPTION

It will be readily understood that the components of the presentinvention, as generally described and illustrated in the Figures herein,may be arranged and designed in a wide variety of differentconfigurations. Thus, the following more detailed description of theembodiments of the invention, as represented in the Figures, is notintended to limit the scope of the invention, as claimed, but is merelyrepresentative of certain examples of presently contemplated embodimentsin accordance with the invention. The presently described embodimentswill be best understood by reference to the drawings.

Referring to FIG. 1, a view of a rotational moving component 106 isshown with magnets 110, 112, 114, and 116 attached thereto. Each of thenorth poles 104, 118, 122, and 128 are alternately arranged with thesouth poles 102, 120, 124, and 130 around moving component 106. Aninductive sensor face 108 is positioned in a fixed position in a closeproximity to magnets 110, 112, 114, and 116 such that when movingcomponent 106 rotates each north pole and each south pole of each magnet110, 112, 114 and 116 pass in front of inductive sensor face 108 causinga magnetic field to penetrate into the sensor face 108. The inductivesensor 142 may have three or more wires for powering the inductivesensor and providing an output of an ON state or OFF state of the sensor142. Moving component 106 may rotate in a clockwise direction 138 or acounter clockwise direction 140.

The inductive sensor face 108 may be positioned perpendicular to anorth-south direction of each of the one or more magnets 110, 112, 114,and 116.

In FIGS. 2a and 2b , timing output diagrams of a sensor system as shownin FIG. 10 is presented for two directions of movement of a movingcomponent such as is shown in FIG. 1. FIG. 2a shows one direction ofmovement with an ON time of an inductive sensor as a function of northand south poles of magnets passing a face of the inductive sensor. FIG.2b is on the same time scale and uses the same rotational speed as isshown in relation to FIG. 2a . The ON time 202 shown in FIG. 2arepresents a first direction of motion and the ON time of FIG. 2brepresents a second direction of motion of a system of the presentinvention. It is clearly evident that the ON time 202 of FIG. 2a is lessthan the ON time 206 of FIG. 2b . Each cycle shown is a result of anorth and south pole of a magnet being rotated past the face of aninductive sensor. When the rotation direction is reversed, the ON timingand OFF timing also change. When the inductive sensor senses thechanging magnetic poles a delay in switching of the output of theinductive sensor takes place. This difference can be utilized todetermine a direction of rotation in accordance with the inventionherein disclosed.

In FIG. 3, a disk 304 is attached to a rotational shaft 310 with magnets306 and 308 on an outer surface of disk 304. Here disk 304 only uses twomagnets 306 and 308. These magnets need not be at 180 degrees separatedfrom each other. Inductive sensor 312 is located at a distance 302 frommagnet 308. Distance 302 is optimally from 0.010 to 1 inch. Inductivesensor 312 may be a Hall effect sensor or other inductive sensor whichis capable of sensing a changing magnetic field.

FIG. 4 shows a top view with magnets inset in a cylinder or disk. Themagnets are arranged with north poles 402, 404, 406 and 408 in a similarside of each magnet and south poles 410, 412, 414, and 416 on similaropposite sides of the magnets. The north and south poles need to beconsistently placed in reference to a similar side of the magnet.Accordingly, poles 402, 404, 406, and 408 can all either be “North”poles or “South” poles. The same is true with poles 410, 412, 414, and416.

FIG. 5 shows a motor 502 with a magnet 508 in a keyway 506 of the motorshaft 504. Here only one magnet 508 is used to determine a direction ofrotation of the motor shaft. The north and south poles of the magnet arerotated past sensor 510 in order to determine a direction of rotation ofthe motor shaft.

In FIG. 6, we have a disk with magnets partially embedded in a face 602of a moving component.

In FIG. 7, a gear system 700 is shown with magnets embedded in gear face702. The gear may be made out of metal, plastic, wood, polymer, carbonfiber, non-ferrous metals, ceramic, rubber, elastomeric compounds,glass, or petroleum.

In FIG. 8, a split rotational component or clamping cylinder 800containing magnets in an outer surface is shown. The magnets may beplace on any surface of the split rotational component which allows thenorth and south poles of each magnet to be rotated past a face of aninductive sensor. The magnets may be embedded, partially embedded or ona surface of a rotational component of the invention. Rotationalcomponent 800 may be split into two sections 802 and 804 by removal offasteners 806. A split rotational component 800 may be fastened on to arotational shaft without removing existing components on a rotationalshaft.

FIG. 9, shows a linear moving component 902 for moving in a linerfashion as indicated at 904.

FIG. 10 is a top view of an extruded rotational cylinder 1002 with aninductive sensor 1006 and magnets in an inner area of the cylinder. Theinductive sensor 1006 is fixed within the extruded cylinder area 1004.This configuration may provide increase protection to the magnets andinductive sensor and may be useful in harsh environments such as minesand other indoor and outdoor hazard areas. The rotational cylinder 1002may be connected to a rotating shaft or driven by a chain or other drivemechanism (not shown).

FIG. 11, shows a schematic block diagram of a system of the presentinvention. A method of determining a direction of movement will bedescribed in relation to this Figure.

Sensor system 1100 is shown with magnets attached to moving component1104, inductive sensor 1102, power supply 1106, ON/OFF timedetermination unit 1108, and rotation direction determination unit 1110.ON/OFF time determination unit 1108 and Rotation direction determinationunit 1110 may be one or more computers or one or more applicationspecific integrated circuit devices. Computer device 1108 may countmagnetic pulses from inductive sensor 1102 in order to additionallydetermine speed and position in addition to direction of movement.Sensor system 1100 may serve as a positional encoder, speed encoder,and/or a directional encoder. Moving component 1104 rotates in a firstknown (clockwise direction) and inductive sensor switches from an ONstate to an OFF state as moving component 1104 rotates. An ON time isdetermined as a function of rotation speed and the ON time is recordedin a memory of determination system 1108. The ON time may be determinedby many different ways which are well known in the art of signalprocessing. Such ways may include positive to negative signaltransitions, sampling within an ON time with a known frequency, etc.After the ON time is determined for the first known direction it isstored in a memory location of determination system 1108. Determinationsystem 1108 may include process and memory, a micro-controller, a dataacquisition device, a computer and program instruction for carrying outfunctions related to ON time detection of a sensor, storage of sensorvalue and comparing of sensor values. Determination system 1108 may alsobe configured to output a determination of a direction of rotation ofmoving component 1104. Next, moving component 1104 is rotated in asecond known, opposite direction (counter clockwise), and the ON time isdetermined and stored in a similar way as that of the first direction.Predetermined bounds or thresholds of the ON times for the first andsecond directions may be set according to statistical curves allowingfor a margin on each side of a fixed value. Next, moving component 1104is rotated in an unknown direction (either clockwise or counterclockwise) and an ON time is determined and compared to the stored ONtime values for known clockwise and counter clockwise rotations. Thedirection is then determined by choosing an ON time value which iscloser to an ON time of a known direction. For example, if the knownclockwise ON time was 6 milliseconds and the known counter clockwise ONtime was 3 milliseconds and the unknown direction ON time was between athreshold of 2-4 milliseconds the determined direction would be counterclockwise. An ON time and/or OFF time and/or ratio of the ON time to theOFF time may be used to determine a direction of movement of acomponent.

Table 1 below shows results of rotation of a moving component 1104 andsampling data points at a fixed rate for ON times (high data points) andOFF time (low data points) for various sensor distances between theinductive sensor and the rotating magnets. Rotational speeds are alsolisted. It should be noted that inductive sensors may be setup in anactive ON or active OFF configuration and the data points may swappositions depending on the hardware setup of the sensor and type ofinductive sensor used. The inductive sensor used in the table below is anormally open type Hall effect proximity sensor. When rotating north andsouth poles of four magnets past a Hall effect sensor in a clockwisedirection at 470 rotations per minute, 16847 samples at 25 kHz wereobtained for an ON state time and when rotated in a counter clockwisedirection about half of the data samples were obtained for an ON state.This shows a significant switching delay between rotation directions andan ON state of the inductive sensor used. The data is consistent evenwhen the speed of rotation is changed.

TABLE 1 direction Hi data pts Low Data pts ratio rpm distance CW 168478753 1.889 470 0.2 CCW 8876 16724 0.5296 490 0.2 CW 16952 8648 1.98381018 0.2 CCW 8574 17026 0.5087 1058 0.2 CW 17415 8185 2.1287 1600 0.2CCW 8293 17307 0.4608 1788 0.2 CW 13796 11804 1.172 529 0.3 CCW 1131114289 0.8027 560 0.3 CW 13791 11809 1.1765 1092 0.3 CCW 11369 142310.8006 1118 0.3 CW 13692 11908 1.1534 1954 0.3 CCW 11288 14312 0.78451770 0.3 CW 13582 12018 1.134 3239 0.3 CCW 11273 14327 0.759 3322 0.3

FIG. 12 is a side view of a power shovel 1200 utilizing sensor system1100, shown in FIG. 11, for motion control feedback of one or moremoving systems of power shovel 1200. Cables 1202, 1204, and/or 1206 maybe connected to a drive system utilizing sensor system 1100 for feedbackcontrol. An inductive sensor and/or one or more magnets of the sensorsystem may be attached to or placed in near proximity to rotationalpulleys, drives, drums, motors, shafts, gears, wheels, rollers, pivots,and/or to linear moving tractor parts such as arms, tracks, shovels,and/or levers. Shovel 1208 may be controlled by one or more motors toperform an automated, repetitive movement to move large amounts ofearth. Position, speed, and direction information may be used to providesoftware safety limits and automated stopping points for movements ofpower shovel 1200. Backwards slippage, over rotation, unexpectedmovement, unexpected positional data, and/or speed deviations may bedetected using sensor system 1100. If brakes are worn, motors fail, orother equipment wear or equipment malfunctions, software safetyparameters may trigger equipment shutdown or automated maintenanceactions.

FIG. 13 is a side view of a dragline 1300 utilizing sensor system 1100,shown in FIG. 11, for motion control feedback of one or more movingsystems of dragline 1300. Cables 1302, 1304, and/or 1306 may beconnected to a drive system utilizing sensor system 1100 for feedbackcontrol. An inductive sensor and/or one or more magnets of the sensorsystem may be attached to or placed in near proximity to rotationalpulleys, drives, drums, motors, shafts, gears, wheels, rollers, pivots1312, and/or to linear moving tractor parts such as arms 1310, tracks,shovels, and/or levers. Shovel 1308 may be controlled by one or moremotors to perform an automated, repetitive movement to move largeamounts of earth. Position, speed, and direction information may be usedto provide software safety limits and automated stopping points formovements of dragline 1300. Backwards slippage, over rotation,unexpected movement, unexpected positional data, and/or speed deviationsmay be detected using sensor system 1100. If brakes are worn, motorsfail, or other equipment wear or equipment malfunctions, software safetyparameters may trigger equipment shutdown or automated maintenanceactions.

FIG. 14 is a side view of a crane 1400 utilizing sensor system 1100,shown in FIG. 11, for motion control feedback of one or more movingsystems of crane 1400. Cables 1402, 1404, and/or tracks 1406 may beconnected to a drive system 1408, 1410 utilizing sensor system 1100 forfeedback control. An inductive sensor and/or one or more magnets of thesensor system may be attached to or placed in near proximity torotational pulleys, drives, drums, motors, shafts, gears, wheels,rollers, pivots, and/or to linear moving tractor parts such as arms,tracks, shovels, and/or levers. A crane hook may be controlled by one ormore motors to perform an automated, repetitive movement. Position,speed, and direction information may be used to provide software safetylimits and automated stopping points for movements of crane 1400.Backwards slippage, over rotation, unexpected movement, unexpectedpositional data, and/or speed deviations may be detected using sensorsystem 1100. If brakes are worn, motors fail, or other equipment wear orequipment malfunctions, software safety parameters may trigger equipmentshutdown or automated maintenance actions.

In FIG. 15, a flow diagram of a servo motor control system and method1500 is shown in accordance with an embodiment of the invention. Incontrol system 1500 a mechanical system 1506 (robotic arm) includes oneor more inductive sensors detecting movement of magnetic north and southpoles of one or more magnets as previously described in relation toFIGS. 1-11. The detected movement provides feedback 1508 to a servocontroller 1504. The feedback may be used to detect position,orientation, direction of travel, or speed of movement of one or morecomponents of mechanical system 1506. A user interface 1502 maycommunicate bi-directionally with servo controller 1504. Programmingwithin servo controller 1504 and/or user interface 1502 may enableprecision control of mechanical system 1506. Safety systems may beimplemented using programming within servo controller 1504 and/or userinterface 1502 and feedback 1508.

In FIG. 16, a flow diagram of a servo motor control system and method1600 is shown in accordance with an embodiment of the invention. Incontrol system 1600 a mechanical system 1608/1610 includes one or moreinductive sensors detecting movement of magnetic north and south polesof one or more magnets as previously described in relation to FIGS.1-11. The detected movement provides feedback 1612 to programmablecontroller 1604. The feedback may be used to detect position,orientation, direction of travel, or speed of movement of one or morecomponents of mechanical system 1608/1610. A user interface 1602 maycommunicate bi-directionally with programmable controller 1604.Programming within controller 1604 and/or user interface 1602 may enableprecision control of mechanical system 1608/1610. Safety systems may beimplemented using programming within controller 1604 and/or userinterface 1602 and feedback 1612. Amplifier 1606 may use feedback 1612as a trigger for timed control signals sent to motor 1608.

In FIG. 17, a flow diagram of a servo motor control system and method1700 is shown in accordance with an embodiment of the invention. Incontrol system 1700 a mechanical system 1710/1712 includes one or moreinductive sensors 1714 detecting movement of magnetic north and southpoles of one or more magnets as previously described in relation toFIGS. 1-11. The detected movement provides feedback 1708 to controller1704 and servo amplifier 1706. The feedback may be used to detectposition, orientation, direction of travel, or speed of movement of oneor more components of mechanical system 1710/1712. A user interface 1702may communicate bi-directionally with controller 1704 and/or servoamplifier 1706. Programming within controller 1704 and/or user interface1702 may enable precision control of mechanical system 1710/1712. Safetysystems may be implemented using programming within controller 1704and/or user interface 1702 and feedback 1708. Amplifier 1706 may usefeedback 1708 as a trigger for timed control signals sent to motor 1710.

In FIG. 18, a perspective view 1800 of servo motor 1802 is shown inaccordance with an embodiment of the invention. Servo motor 1802includes an inductive sensor 1810 mounted to or integrally formed into aservo motor housing 1802. Servo motor shaft 1804/1806 includes at leastone magnet 1812 with north 1814 and south 1816 poles of magnet 1812arranged to each intersect a face 1818 of inductive sensor 1810. Servomotor 1802 includes control lines 1808 for controlling servo motor 1802.Inductive sensor 1810 may be a hall effect sensor and may be removablefrom motor 1802 or integrally formed within the housing of servo motor1802. Signals produced by inductive sensor 1810 provide feedback todetect position, orientation, direction of travel, or speed of movementof servo motor shaft 1804/1806. Motor control systems and motor safetysystems may be implemented using signals produced by inductive sensor1810 along with programming within a servo controller and/or userinterface to limit travel, limit current, limit torque, limit position,limit speed, or limit orientation of shaft 1804/1806.

The apparatus and methods disclosed herein may be embodied in otherspecific forms without departing from their spirit or essentialcharacteristics. The described embodiments are to be considered in allrespects only as illustrative and not restrictive. The scope of theinvention is, therefore, indicated by the appended claims rather than bythe foregoing description. All changes which come within the meaning andrange of equivalency of the claims are to be embraced within theirscope.

The invention claimed is:
 1. A servo motor system comprising: one ormore magnets fixed to a moving component of the servo motor system, eachof the one or more magnets having a north pole and a south pole alignedto alternately induce a magnetic field into a face of an inductivesensor; a processor and memory non-transitively programmed to: determinean ON time of the inductive sensor as a result of moving the north poleand the south pole of each of the one or more magnets past the inductivesensor in an unknown direction; determine the unknown direction to be aknown first direction or a known second direction when the ON time isequal to a predetermined threshold associated with the first knowndirection or a predetermined threshold associated with the second knowndirection; and one or more servo motors that receive control signals asa result of the moving of the north poles and the south poles of each ofthe one or more magnets past the inductive sensor, wherein the one ormore servo motors cause motion of a mechanical system.
 2. The servomotor system of claim 1, wherein the mechanical system is a robotic arm,an assembly line, or an electro-mechanical machine.
 3. The servo motorsystem of claim 2, wherein the unknown direction is a rotationaldirection.
 4. The servo motor system of claim 2, wherein the unknowndirection is a linear direction.
 5. The servo motor system of claim 1,wherein the inductive sensor additionally detects speed or position. 6.The servo motor system of claim 1, wherein the inductive sensor is ahall effect sensor.
 7. The servo motor system of claim 1, wherein theinductive sensor is mounted to a servo motor or to a servo motor cover.8. The servo motor system of claim 1, wherein the face of the inductivesensor is positioned perpendicular to a north-south direction of each ofthe one or more magnets.
 9. The servo motor system of claim 1, whereinthe face of the hall effect sensor is positioned between 1 and 0.010 ofan inch from a surface of the one or more magnets.
 10. The servo motorsystem of claim 3, wherein a speed of the rotation direction is between1 and 20,000 rotations per minute.
 11. The servo motor system of claim1, wherein the one or more magnets are attached to a rotational drivesystem.
 12. The servo motor system of claim 1, wherein the servo motorsystem additionally comprises one or more cable drive systems.
 13. Theservo motor system of claim 12, wherein the inductive sensor providesdirection, position, and location of at least one cable of the cabledrive systems.
 14. The servo motor system of claim 12, wherein theinductive sensor provides signals that improve safety and control of themechanical system.
 15. The servo motor system of claim 14, whereinpositional safety threshold parameters related to direction of rotationare used to achieve the improved safety and control.
 16. The servo motorsystem of claim 14, wherein a load weight is determined using signalsfrom the inductive sensor and motor current.
 17. The servo motor systemof claim 16, wherein the load weight is a weight exerted on the one ormore cable drive systems.
 18. The servo motor system of claim 17,wherein the mechanical system comprises two or more cable drive systems.19. The servo motor system of claim 18, wherein the mechanical device isa manufacturing tool.
 20. The servo motor system of claim 19, whereinthe mechanical system is controlled in part by feedback produced by theinductive sensor.